There are ten Heavenly Stems (represented by the acronyms "H" or "HS") used in the construction of the Four Pillars of Ba Zi (四柱八字), a method of Chinese Divination based on a person's date and time of birth. For example, both the acronyms "HS1" and "H1" represent the first Heavenly Stem, namely "Jia" (Yang Wood), as shown in the tables below.